The study of photoelectrochemical water splitting using n-GaN with NiOx & CoOx nanoparticles coating as the photoelectrodes

Abstract

Hydrogen generated by photoelectrochemical solar water splitting process has a great potential to provide the energy consumption Gallium nitride (GaN) is the materials appropriate for solar water splitting system because its energy band position straddles the redox potential of water However n-type GaN (n-GaN) as photoanode has photo-corrosion event in the long-term experiment In this research we discuss the characteristics and photoelectrochemical (PEC) properties of Nickel Oxide (NiOx) and Cobalt Oxide (Co3O4) nanoparticles on n-GaN substrate by spin coating process The various weight ratio of NiOx (1:5 and 3:2) and Co3O4 (1:1 and 1:5) were utilized in this study These catalysts were covered on n-GaN to prevent photo-corrosion and decrease the solar water splitting reaction overpotential Interestingly NiOx nanoparticles can not only avoid the corrosion phenomenon on n-GaN surface but also enhance photocurrent density while working electrode applied bias of 1V in two-electrode system In stability test the hydrogen evolution rate of NiO 3:2 was more rapid than the pristine n-GaN after 5 hours This result indicates that NiOx nanoparticles covered on n-GaN can enhance lifetime and hydrogen production in PEC cells

Date of Award	2019
Original language	English
Supervisor	Jinn-Kong Sheu (Supervisor)